Leakproof cover for bell and spigot pipe-joints



Dec. l

R. M. MCCALLEY V LEAKPROOF COVER FOR BELL AND SPIGOT PIPE JOINTS FiledJune 29, '1926 Patented Dec. 1, 1931 BDEBICK H. HCOALLE'Y, OF PORTLAND,OREGON LEAKPBOOF @OVER FOR BELL AND SPIGOT PIPE-JOINTS Appmamn mea :runeas, 192s. semi No. 119,341.

My invention relates to cast iron or steel pipes installed or to beinstalled for distributing gas or water or for sewage disposal,

' in which class the sections are generally con- I nected by abell-and-spigot joint.-

To better describe the purpose and utility of my invention, it isconvenient to refer briefly to the resent methods for renderin thesepipe-joints leak proof. The 'oint lo reerred to consists in an enlargedell shaped socket on one end of the pipe into which the spigot end ofthe next adjoining length or section of pipe is inserted. An annularspace is provided within the bell or socket to receive packing materialwithv which to lill up the space to make the joint tight.

The mode of packing the joint usually used is to insert and pack, orcalk, into place several layersof yarn or oakum. Pig lead is then heatedand poured into the joint, the yaii or oakum forming a backing for thelea These joints, inevitably leak due to subsequent movement of thepipe, caused by settling of the, pipe, traffic vibrations, orunderground construction work. The movement of the pipe is also causedby a creeping action, due to the eil'ects of contraction and expansion.All of these factors affect the tightness of the joint; for sinceleadhas little resiliency any subsequent movement of the pipe tends tocause a permanent set in the lead, and small fissures result which allowleakage.

Several means have been devised to cover the pipe joints so as toprevent leakage, such means employing clamps in some' formor other, anddepending for their eli'ectiveness l 40 upon the compression either of`two metal surfaces together, or upon a gasket placed between thecompressed metal surfaces.

But experience has demonstrated that a pipe-joint of the characterdescribed which depends for its tightness upon the compres'- sion of twometal surfaces together or u on a gasket between them. is not relia le.Clamps are unsatisfactory because they provide no stability in theensealing me'ans of whichthey constitute a-part, for they will inevitablbe subjected to a movement of the connecte pipe section but are notcapable of accommodating such movement.

Therefore, it has been attempted to enclose the pipe joint with anensealing jacket made of lead, aseillustrated, for exam le, by theUnited States patent granted to orbin March 25, 1902, No. 696,316.Butthe ends of this ensealing jacket were also secured by clamps to theconnected pipe sec- 00 tion, and hence theunsatisfactory character ofthe latter is present just the same. Lead being a soft metal, having butlittle resiliency, would be subject to the same action as the originallead packing of the pipe- 05 joint and therefore, the ineiicieney ofsuch packing has not been overcome.

My observations have convinced me that some harder metal and greatertensile strength than leadl must be used as an en- 'lo sealing jacket orcover for the joint and that clamps as the connecting means will not do.Since cast iron and steel are to be used for making the pipe sections,the ends of the cover of its joints must be unitedwith the l pipesections, and the connection so produced must be of such nature that theunited pipe sections and the cover constitute a homogeneous, continuous,integral structure; homogeneous in the sense that the parts so unitedincluding the band between them must be suliiciently similar incharacter as in eect to constitute a substantial unit adapted in all itscomponents to yield to the relative movements of the pipe sections afterhaving been installed. vThe soldering of the ends of the ensealingjacketvto the connected pipe sections would not be practicable becausethe solder would .o

not hold vunder any relative movements of the connected pipe sections. Q

I attain my object of rendering said p'pe joint leak proof-by enclosingthe joint in a cover forming a continuous integral structure with theconnected pipe section; said cover consisting of an annular collar ofductile metal suitable for welding; the collai` being mounted on thespigot-end ofone pipe section and coverin the mouth of the lend of theother p1 e section, the exterior peri hery 'of said col ar coincidinwith that of tlie rim of said mouth; and t e interior periphery of saidcollar being welded to the circumference of said spigot-end, and theexterior. peripheryof said collar being welded to the rim of the mouthof said bell; the form of the collar and the ductile character of themetal of which it is made adapting ,it to accommodate the relativemovements lof the connected pipe-section with each other, therebypreventing the rupture' of the integral character ofthe pipe structureby vsaid movements.

In order'to make full provision for the relative movements of theconnected pipesection, when such movements may be looked for in greaterdegree by reason of climatic or other conditions, I make the collarconical, and of more or less angular form in longitudinal section.

Furthermore, when my method is to be used for the joints of an installedpi e, I make my collar of two longitudinally divided half-sections, thelongitudinal seams of which half sections are welded together after theyhave been put in place, to make the collar itself an integral unit.

Furthermore, my method of rendering the joints of a bell-and-spigot-pipeleak proof,

incidentally increases the strength of the resulting joint, and in sodoing permits the use of greater pressure than the ordinary joints osuch pipes would stand.

The growth of mostgas or water distribution systems requirea constantincrease in the internal pressure, and therefore, some eiiicient methodof preventing leakage at the joints is necessary. My method permits theincrease of the iinternal pressure up to the strength of the pipeitself, and at the same time msures tightness of the joint even withsuch increased pressure. Such results could not be obtained by any merecalking method; nor by any method such as described for example in saidCorbin patent.

The further details .of my ,invention and the manner of practicing thesame are hereinafter fully described with reference to the accompanyingdrawings, in which Fig. 1 illustrates one embodiment of my invention ina pipe joint for rendering the4 same leak-proof; the illustration hereshown representing my invention as comprising a lcollar of annular,partly conical form, and

more or less of angular form in longitudinal section, so that the collarby flexing under the relative movements of the connected pipe section isadapted toi accommodate such movement;

Fi 2 shows a somewhat similar but simp er method for carrying myinvention into practice; and also shows the providing oiga removable lugin the ensealing collar, so as to permit t e escape of gases where myinvention iis applied to render joints leakroof, thus preventing t eaccumulation o an explosive mixture under the unsealing collar; and

Fig. 3 is a still sim ler form of practicing my invention, as willhereinafter be more fully described. f

In the drawings, I have designated like parts by like referencecharacters, but with numerical exponents referring to the respectivefigures of which they are a part.` i a represents the spigotend of acast iron pipe which is usually provided with., an annular bead (i. l

b represents the socket or bell-end of a cast iron pipe, usuallyprovided with an enlarged cross section at the face c.

The joint packing material ma becom-l ing the latter. The collar isthen-.welded to the spigot-end of the pipe section at and to as-main jthe rim of the bell or mouth of the ot er pipe section as at k.

The lead packing in the bell should first be recalked to in ure thetemporary stopping of leakage, i/f an v The small recess left at theface c of the bell as a result of calking the lead in the originalinstallation, as well as from the recalking is preferably filled with aiheat resistant non-shrinking retort cement, h,

thereby to protect the lead packing from the heat developed during theweldlng of the ends of the collar on the connected pipe sections.

The form of collar illustrated by Figs. 1 and 2 is especially adaptedfor use on gas mains. A Ventilating opening o having a removable plug isprovided to prevent the accumulation of an explosive mlxture of gases.The plug may be threaded into the vent-opening and the plug issubsequently brazed or welded to insure a ainst leakage.

The forms of colar used in Figs. l and 3 are designed to allow movementof the confinduced by temperature changes approaches the unit Workingstrength of the material of the pipe. And as a factor of safety, it isadvisable to provide an efficient means to provide in the collarstructure for any movement of the connected pipe sections.

To illustrate the collars under contraction,

I will take the approximate forms indicated" by the dotted lines i inFig. 1 and by 3 in Fig. 3. j

Under ordinary circumstances the collar z' can be made of low carbonsteel. Other cases may arise Where more ductile material such as copperor compounds thereof may be deemed preferable. To accommodate themovements of connected pipe-sections, this collar is made of annularconical form and more or less angular in longitudinal section.

Installations in corrosive soils may require the use of anti-corrosivematerial, such as copper bearing steel, or the use of protectivecoatingmediums such as asphalt dips.

The collars i and 2 in Figs. 1 and 2 are of conical or partially conicalform so as to extend back away from the face of the bell c to the pointj on the spigot-end, in order to keep the heat due to welding away fromthe lead packing in the bell, a sufficient distance to prevent the leadfrom being melted and running into the interior vof the pipe to form anobstruction. This distance will vary with j the diameter, andconsequently the thickness,

of the material in the pipe.

The thickness of the bell at c is sufficient to prevent excessive heattransmission to the lead packing f. The location of the welding at pointy' is preferably removed a distance of from f1 to 6 inches away from thelead pack- IVith large pipe having relatively thick cross section, theannular collar i3 shown in Fig. 3 may be used, since the effect of theheat developed in Welding is not so readlly transmitte-d to the leadpacking as with pipes with rthinner cross section.- The accommodationtype of collars shown in Figs. 1, 2 and 3 is negligible. Y

My method can, of course, be used for repairing lines already laid `andin sewers, or new installations.

When new pipe is put into pla-ce only sufficient pa 'ng to hold the pipein proper alinemsen is required. This packing can be of any inexpensivematerial. such as rope yarn. The lead acking and the heat reslstantpaste may. e omitted.

The welding can be done either with the acetylene, hydrogen or electricwelding process using either bronze or iron welding rods.

The Welding process which I prefer is one utilizing a relatively lowflame temperature; for example, satisfactory welds can be secured byusing bronze rods and hydrogen gas, since the flame temperature can thusbe kept down to approximately 1200 degrees Fahrenheit. This relativelylow tempreature has little effect upon the cast iron of the pipe,

and therefore does not reduce the tensile strength thereof.

My method gives a positive means of eliminating all leakage from thejoint, and is unaffected by subsequent movement 'of the pipe being an4integral part thereof. This efficiency of the weld, which is ofparamount consideration can be increased, and the time required forwelding, consequently the cost of welding decreased, by firstjgrindingthe surface of the cast iron pipe at the points y' and lo, this grindingproviding a smooth surface to receive the molten welding materialinsuring an efficient bond.

I claim:

' l. Incombination with a bell-and-spigot cast-iron pipe joint, a leakproof cover comprising, 2in-elongated collar of flexible metal, one endvof the collar being enlarged to conform with the rim of thebell-section of the joint and being welded thereto, the opposite y 2. Aplurality of pipe sections joined by a bell and spigot joint and aleakproof cover for said joint; said cover comprising an elongatedcollar of fiexible material, one end of the collar conforming with thecircumference of the rim of the bell section ofthe joint, the oppositeend conforming with the circumference of the spigot section, saidleakproof collar being secured to the pipes by Welding and non-shrinkingretort cement within the space between the collar and the loint.

J 3. A pair of pipe sections engaging each cother with a bell-and-spigotjoint, packing material within said bell having a melting point low withrespect to that of the material of the pipe, an elongated collarsurrounding said joint to provide a leakprof cover therefor, one end ofsaid collar conformin with the circumference of the bell and bemg weldedthereto, the opposite end kof said collar conforming with thecircumference of the spi ot section and welded thereto a substantiedistance from the bell, and non-shrinkin refractory cement covering themouth o the bell whereby the pack- 'ing material is held in lace should1t become liqueed during t e welding operations.

RQDERICK M. MGCALLEY.

